The invention relates to an apparatus for hooping a package, for example a stack of newspapers, by means of a band. The apparatus has a horizontal conveyor defining a conveying plane and conveying the package rectilinearly into and beyond a hooping position. The apparatus further has a band guide channel forming a loop and having open or openable wall regions to allow the band loop formed therein toe be pulled out when it is applies to the package, and a binding head for inserting the band into the band guide channel and for tensioning, joining and severing the band. The hooping plane defined by the band applied to the package extends in the conveying direction.
An apparatus of this kind is known from German Offenlegungsschrift 33 03 956, FIG. 3. In this cross-hooping machine only the band guide channel for longitudinal hooping is of interest in connection with the present invention. It is constructed as a vertical frame extending in the conveying direction, in such a manner that the front and rear portions of the frame can be pushed up in order to bring the package into the hooping position and to convey it further.
Apart from the complicated construction required for band guide frame divided in this manner and comprising movable portions, the time needed for the hooping operation is considerable and consequently the efficiency of this machine is inadequate. The insertion of the band cannot start until the package has assured its hooping position and the band guide frame has been closed.
Another apparatus of the kind first defined above is known from German Offenlegungsschrift 41 00 276. In this known binding machine the band guide channel for longitudinal hooping of interest here is stationary and disposed on one side of the hooping plane, while the other side remains free. This requires a spatial shape of the band guide channel which does not coincide with the hooping plane. During the tensioning operation the inserted band loop is pulled laterally or obliquely out of the uneven band guide channel and slides over guide plates before being finally laid tightly against the package in the hooping plane.
This known arrangement of the band guide channel has the consequence that the loop length required on insertion, and consequently the excess length of band to be pulled back in the tensioning operation, is considerable. This has a negative effect on the cycle time and thus on the performance of the machine. Because of the necessary slight inclination of the guide plates, the speed at which the band is pulled during tensioning is limited. In addition, only particularly stiff grades of band can be used. Finally, difficulties arise in respect of the conveyor means that can be used.